Navigation Links
Copy of the genetic makeup travels in a protein suitcase
Date:5/25/2012

The blueprint of all living beings is stored in their genetic material. In higher organisms this is stored in the well-protected cell nucleus. "Here a kind of copier works around the clock to make copies of the information needed at the time," says first author Jan Peter Siebrasse from the Institute for Physical and Theoretical Chemistry at the University of Bonn. The copies contain the information which the cells need to produce vital enzymes or other cell building materials. These copies consist of messenger RNA which travels on random paths to the membrane of the cell nucleus and from there through the nuclear pores into the cytoplasm which fills out the cells like jello.

Stringent quality control at the pore

The working group has found out that the messenger RNA lingers briefly at the pores in the membrane of the nucleus before it is finally transported out presumably for a final "quality control" or simply because it has to adjust in order to leave via the pore exit. The export process lasts in total only a few hundredths of a second to several seconds. "In all likelihood, the process needs much longer for larger, voluminous messenger RNA molecules than for smaller ones," adds Prof. Ulrich Kubitscheck, head of the working group Biophysical Chemistry and senior author of the publication.

Interestingly enough, only about every fourth collision between arriving messenger RNA and the cell nucleus leads to a successful export. Here, two kinds of processes can be distinguished: On the one hand, brief collisions with the nuclear membrane where presumably no pore is hit, and, on the other hand, those transports that are slowly aborted perhaps on account of a deficient quality control.

RNA is packed in a suitcase made of "protein"

The RNA is packed in a type of "suitcase" made of proteins for transporting. "And it is quite a chunk," grins Prof. Kubitscheck. This is why some of his colleagues presume there are helpers on the outside of the cell's nucleus which pull the "suitcase" through the pores, a theory which the professional physicist together with the molecular biologist Jan Peter Siebrasse are currently investigating

Just what exactly happens en route from the copier to the pores has been clarified in recent years among others by Prof. Kubitscheck's working group at the University of Bonn. "Key experiments on this were undertaken by the biologist Dr. Roman Veith, whose doctorate thesis was awarded this year's Dr. Edmund ter Meer Ph.D. thesis prize from the university society," reports Prof. Kubitscheck. For these experiments the messenger RNA was altered so that it glowed when illuminated with a laser beam. This enabled the researchers to trace the path of individual molecules containing copies of the genetic material in living buccal gland cells of a mosquito type with up to 500 pictures per second. A light microscope with a high speed camera made the observation possible.

Researchers constructed special light microscope

Once the transport processes between the "copier" and the cell nuclear membrane were understood, Prof. Kubitscheck and his colleagues turned their attention in recent years to the direct transport process through the nuclear pores. In order to observe this process, they took a number of years to construct a highly sensitive light microscope which works on the basis of target illumination. It creates delicate pictures of living samples and, in the process of taking pictures with high frequency, creates an unusually strong contrast.

Process is of fundamental biological interest

The question of how the messenger RNA enters the cell from the cell nucleus is of fundamental interest in biology, a fact Prof. Thoru Pederson (University of Massachusetts Medical School) underscores in his comment which accompanies the article paper presented by the Bonn-based scientists. In recent years, there have been two publications on this performed by working groups in the USA and Israel. In these studies, however, the messenger RNA has been altered with additives making the molecules at least double their volume. By contrast, the Bonn-based working group modified the messenger RNA in a negligible way, as Prof. Pederson determined.


'/>"/>
Contact: Dr. Ulrich Kubitscheck
u.kubitscheck@uni-bonn.de
49-228-732-262
University of Bonn
Source:Eurekalert

Related biology news :

1. Rare genetic disorder gives clues to autism, epilepsy, mental retardation
2. Genetic Engineering & Biotechnology News reports on growing role of molecular diagnostics
3. Study finds genetic variant plays role in cleft lip
4. Genetic finding implicates innate immune system in major cause of blindness
5. American College of Medical Genetics receives $13.5M NIH contract
6. Clue to genetic cause of fatal birth defect
7. Can genetic information be controlled by light?
8. The American Society of Human Genetics hosts 58th Annual Meeting in Philadelphia
9. Modern genetics vs. ancient frog-killing fungus
10. Genetic based human diseases are an ancient evolutionary legacy
11. Genetic evidence for avian influenza movement from Asia to North America via wild birds
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/19/2016)... 2016 The new GEZE SecuLogic ... web-based "all-in-one" system solution for all door components. It ... the door interface with integration authorization management system, and ... The minimal dimensions of the access control and the ... installations offer considerable freedom of design with regard to ...
(Date:4/15/2016)... DUBLIN , April 15, 2016 ... of the,  "Global Gait Biometrics Market 2016-2020,"  report ... http://photos.prnewswire.com/prnh/20160330/349511LOGO ) , ,The global gait ... CAGR of 13.98% during the period 2016-2020. ... movement angles, which can be used to compute ...
(Date:4/13/2016)...  IMPOWER physicians supporting Medicaid patients in ... standard in telehealth thanks to a new partnership with ... IMPOWER patients can routinely track key health measurements, such ... and, when they opt in, share them with IMPOWER ... local retail location at no cost. By leveraging this ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... , June 23, 2016 A person commits ... the crime scene to track the criminal down. ... U.S. Food and Drug Administration (FDA) uses DNA evidence to ... Sound far-fetched? It,s not. The FDA has ... to support investigations of foodborne illnesses. Put as simply as ...
(Date:6/23/2016)... ... June 23, 2016 , ... Charm Sciences, Inc. is pleased ... received AOAC Research Institute approval 061601. , “This is another AOAC-RI approval of ... Salter, Vice President of Regulatory and Industrial Affairs. “The Peel Plate methods perform ...
(Date:6/23/2016)... , June, 23, 2016  The Biodesign Challenge ... envision new ways to harness living systems and biotechnology, ... Art (MoMA) in New York City ... 130 participating students, showcased projects at MoMA,s Celeste Bartos ... Paola Antonelli , MoMA,s senior curator of architecture and ...
(Date:6/23/2016)... ... 2016 , ... Supplyframe, the Industry Network for electronics hardware ... . Located in Pasadena, Calif., the Design Lab’s mission is to bring together ... built and brought to market. , The Design Lab is Supplyframe’s physical representation ...
Breaking Biology Technology: